Well just for jollies, I decided to see if a hash reference works with a Scale, and it DOES. So I guess the Scale widget likes scalar refs and hash refs, but NOT array refs.

#!/usr/bin/perl
use warnings;
use strict;
use Tk;


my %svals =(
 1 =>{
            'object' => undef,
            'value'  => 0,
           },

 2 =>{
            'object' => undef,
            'value'  => 0,
           },
 3 =>{
            'object' => undef,
            'value'  => 0,
           },
 4 =>{
            'object' => undef,
            'value'  => 0,
           },
       );

# window setup  
my $mw = MainWindow->new;

foreach my $i (1 .. 4) {
  $svals{$i}{'object'} = $mw->Scale(
      -from    => 30,
      -to    => 0,
      -orient    => 'vertical',
      -variable    => \$svals{$i}{'value'},
     )->pack(-side    => 'left');
}


foreach my $i (1 .. 4) {
   $svals{$i}{'value'} = 7*$i;
}

MainLoop;
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